title: Serum vitamin D levels in free-ranging koalas (Phascolarctos cinereus).
abstract: Due to climatic conditions in Northern America and Europe, koalas (Phascolarctos cinereus) are often housed indoors. Koala joeys raised in these environments are susceptible to the development of metabolic bone disease due to a lack of exposure to solar ultraviolet radiation to themselves and their dam. As an initial step toward describing vitamin D sufficiency and adequately measuring responses to supplementation, vitamin D values were calculated by using serum collected from 20 free-ranging koalas on St. Bees Island, Queensland, Australia. Vitamin D values ranged from 8.1 to 30.4 pg/ml (18.4 +/- 5.5 pg/ml) for 1, 25-hydroxyvitamin D, and from 1 to 14 nM/L (7.4 +/- 3.0 nM/L) for 25-hydroxyvitamin D. These koala serum vitamin D values are unusually low when compared with eutherian mammals. Although this study was limited in numbers and in the geographically range of the koalas sampled, it does suggest that the koala's requirement for vitamin D is low. Therefore, supplementation to prevent disease may be relatively easy to achieve because low doses will likely meet requirements. Caution should be taken to avoid intoxication if supplementing vitamin D in koalas.
authors.affiliation: San Diego Zoo, San Diego, California 92101, USA. gpye@sandiegozoo.org
authors.forename: Geoffrey W
authors.initials: GW
authors.lastname: Pye
authors.forename: William
authors.initials: W
authors.lastname: Ellis
authors.forename: Sean
authors.initials: S
authors.lastname: FitzGibbon
authors.forename: Brian
authors.initials: B
authors.lastname: Opitz
authors.forename: Laura
authors.initials: L
authors.lastname: Keener
authors.forename: Bruce W
authors.initials: BW
authors.lastname: Hollis
mesh_terms: D000818:Animals; D005260:Female; D008297:Male; D048368:Phascolarctidae / Q000097:blood*; D014807:Vitamin D / Q000097:blood*
chemical_list: D014807:Vitamin D